US20060074381A1 - Medical device initialization method & system - Google Patents

Abstract

A system includes a remote controller and an infusion pump. The infusion pump includes an RF telemetry portion configured to receive an RF data signal from the remote controller. A processing portion is configured to process the RF data signal received by the RF telemetry portion. A dispensing apparatus, responsive to the processing portion of the medical device, dispenses medicament in accordance with the RF data signal. The dispensing apparatus includes a fill sensor for providing an initialization signal to the processing portion of the medical device upon the dispensing apparatus being filled with at least a defined volume of medicament.

Description

RELATED APPLICATIONS
• This application claims the priority of the following applications, each of which is herein incorporated by reference: U.S. Provisional Application Ser. No. 60/466,708, entitled “Infusion Device System Hardware and Method of Using The Same”, filed 30 Apr. 2003; U.S. Provisional Application Ser. No. 60/466,704, entitled “Infusion Device System Programming and Method of Operating an Infusion Device”, filed 30 Apr. 2003; and U.S. Provisional Application Ser. No. 60/466,589, entitled “Remote Communications Methods for Infusion Devices”, and filed 30 Apr. 2003.
FIELD OF THE INVENTION
• This invention relates to medical devices/systems and, more particularly, to medical devices/system having RF communication capabilities.
BACKGROUND
• Ambulatory infusion devices/pumps were developed to deliver liquid medicaments to patients. Typically, infusion devices are capable of providing sophisticated fluid delivery profiles (e.g., bolus doses, continuous basal infusions, variable flow delivery rates, etc.) and often automate the delivery of insulin when treating diabetes.
• Currently available ambulatory infusion devices are typically bulky, heavy, expensive and fragile. Additionally, these devices are typically difficult to program and prepare for infusion. Further, filling these devices with the medicament can be difficult and often requires that the user carry both the medicament and the filling accessories. Often, these devices require specialized care, maintenance, and cleaning to assure proper functionality and safety for their intended long term use. Unfortunately, as these devices tend to be expensive, healthcare providers typically limit the patient populations to which these devices are made available.
SUMMARY OF THE INVENTION
• According to an aspect of this invention, a system for delivering a fluid to a patient includes a remote controller and an infusion pump. The infusion pump includes an RF telemetry portion configured to receive an RF data signal from the remote controller. A processing portion is configured to process the RF data signal received by the RF telemetry portion. A dispensing apparatus, responsive to the processing portion of the medical device, dispenses medicament in accordance with the RF data signal. The dispensing apparatus includes a fill sensor for providing an initialization signal to the processing portion of the medical device upon the dispensing apparatus being filled with at least a defined volume of medicament.
• One or more of the following features may also be included. The defined volume of medicament (e.g., insulin) may be fifty units. The dispensing apparatus may include a fluid reservoir and the fill sensor may be a normally-open mechanical switch that closes upon the reservoir being filled with the at least a defined volume of medicament.
• According to another aspect of this invention, a medical device includes an RF telemetry portion configured to receive an RF data signal. A processing portion is configured to process the RF data signal received by the RF telemetry portion, and a dispensing apparatus, responsive to the processing portion of the medical device, dispenses medicament in accordance with the RF data signal. The dispensing apparatus includes a fill sensor for providing an initialization signal to the processing portion of the medical device upon a fluid reservoir of the dispensing apparatus being filled with at least a defined volume of medicament.
• One or more of the following features may also be included. The defined volume of medicament (e.g., insulin) may be about one half of the volume of the fluid reservoir. The fill sensor may be a normally-open mechanical switch that closes upon the fluid reservoir being filled with the at least a defined volume of medicament.
• Upon receipt of the initialization signal by the processing portion, the RF telemetry portion may periodically poll a defined RF frequency to determine if the RF data signal is available for receipt. The defined RF frequency may be within a frequency band of 13.40-13.70 megahertz. The RF telemetry portion may be configured to receive data encoded within a 13.56 megahertz carrier signal and/or transmit data encoded within a 13.56 megahertz carrier signal.
• The RF telemetry portion may include a compact antenna (e.g., a spirally-wound or helically-wound antenna). The effective length of the compact antenna may be a defined percentage of a wavelength of a carrier signal.
• The processing portion may include a main processing unit, and an interlock processing unit. The RF data signal may include a defined validation sequence and the RF telemetry portion may be configured to examine the RF data signal to confirm that the RF data signal includes the defined validation sequence. The RF telemetry portion may be configured to transmit an acknowledgement signal to the device transmitting the RF data signal if it is determined that the RF data signal includes the defined validation sequence. The RF telemetry portion and at least a first portion of the processing portion are incorporated into a single microchip (e.g., an application-specific integrated circuit).
• According to another aspect of this invention, a method of extending the shelf life of a medical device includes placing the medical device into a low-power sleep mode. The medical device includes a processing portion and a dispensing apparatus. The dispensing apparatus is filled with at least a defined volume of a medicament, and an initialization signal is provided to the processing portion of the medical device.
• One or more of the following features may also be included. The medical device may include an RF telemetry portion. The RF telemetry portion may periodically poll a defined RF frequency to determine if an RF data signal is available for receipt. The defined RF frequency may be within a frequency band of 13.40-13.70 megahertz.
• If the RF data signal is available for receipt, the RF data signal may be examined to confirm that the RF data signal includes a defined validation sequence. An acknowledgement signal may be transmitted to the device transmitting the RF data signal if it is determined that the RF data signal includes the defined validation sequence.
• The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features and advantages will become apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a diagrammatic perspective view of a fluid delivery system, including an infusion pump and a remote controller;
• FIG. 2 is an isometric top view of the infusion pump ofFIG. 1;
• FIG. 3 is an isometric bottom view of the infusion pump ofFIG. 1;
• FIG. 4 is an isometric view of the infusion pump ofFIG. 1 (with the upper housing removed); and
• FIG. 5 is a front view of the remote controller ofFIG. 1; and
• FIG. 6 is a diagrammatic view of the infusion pump ofFIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• Referring toFIGS. 1-4, there is shown a remotely-controlled,disposable infusion pump10, which is typically used with remote controller100 (shown inFIGS. 1 and 5). Examples of similar infusion pumps are disclosed in co-pending U.S. patent application Ser. No. 09/943,992, filed on Aug. 31, 2001, which is herein incorporated by reference.Infusion pump10 may incorporate a new and improved RF telemetry processor and local processor, which are discussed below in greater detail and shown inFIG. 6.
• While the new and improved RF telemetry processor and local processor of the present disclosure are described with reference the exemplary embodiment ofinfusion pump10 andremote controller100, it should be understood that the present disclosure is broadly applicable to any form of programmable infusion pumps. For example, the new and improved RF telemetry processor and local processor of the present disclosure may be used with programmable ambulatory insulin infusion pumps of the sort currently commercially available from a number of manufacturers, including without limitation and by way of example, Medtronic Minimed under the trademark PARADIGM, Animas Corporation under the trademarks IR 1000 and IR 1200, Smiths Medical under the trademark Deltec COZMO, DANA Diabecare USA, and others.
• Infusion pump10 is used to deliver mendicants to a person or animal. The types of mendicants that may be delivered (via infusion pump10) include, but are not limited to, insulin, antibiotics, nutritional fluids, total parenteral nutrition (i.e., TPN), analgesics, morphine, hormones/hormonal drugs, gene therapy drugs, anticoagulants, analgesics, cardiovascular medications, AZT, or chemotherapeutics, for example. The types of medical conditions that infusion pump10 may be used to treat include, but are not limited to, diabetes, cardiovascular disease, temporal pain, chronic pain, cancer, AIDS, neurological disease, Alzheimer's Disease, ALS, Hepatitis, Parkinson's Disease or spasticity, for example.
• Infusion pump10 is typically disposable and adapted for attachment to the skin of a patient for infusing a mendicant, such as insulin, into the patient on a regular basis. Theinfusion pump10 may have a usable life of about 72 hours, for example, before being removed from the patient and discarded.
• Referring toFIG. 4, infusion pump10 typically includes adispenser assembly12 for causing mendicant fromfluid reservoir14 to flow throughflow path assembly16 to transcutaneous access tool (e.g., needle)18 for infusion into the patient. The volume ofreservoir14 is chosen to best suit the therapeutic application ofinfusion pump10, impacted by such factors as the available concentrations of mendicant to be delivered, the acceptable time between refill/disposal ofinfusion pump10, and size constraints, for example
• Local processor20 (e.g., one or more processors or electronic microcontrollers) is connected todispenser assembly12, and is programmed to control the flow of mendicant to thetranscutaneous access tool18 based on flow instructions from the separate, remote controller100 (as shown inFIG. 5).RF telemetry processor22, which is coupled tolocal processor20, receives flow instructions fromremote controller100 and provides them tolocal processor20.
• Infusion pump10 typically includes a power supply (e.g., a battery or capacitor; not shown) that supplies power tolocal processor20. This power supply may be non-serviceable (e.g., a litium ion battery soldered to a circuit board) or replaceable (e.g., a AAA battery).
• As shown inFIG. 4,infusion pump10 may also include various sensors/transducers, such as a flow condition sensor assembly (not shown) or a fill sensor24 (to be discussed below in greater detail), that transmit information tolocal processor20 concerning the condition and status ofinfusion pump10.
• Infusion pump10 includeshousing26, which contains and protectsdispenser assembly12,reservoir14,flow path assembly16,transcutaneous access tool18,local processor20, andRF telemetry processor22.Infusion pump10 may be provided with an adhesive layer28 (as shown inFIG. 3) on thelower surface30 ofhousing26 for temporarily securinginfusion pump10 directly to the skin of the patient.
• As discussed above,infusion pump10 includesRF telemetry processor22 that facilitates the programming oflocal processor20 viaremote controller100. Commands may be transmitted betweeninfusion pump10 andremote controller100 via a communication circuit (not shown) incorporated intoremote controller100.
• The outer surfaces ofhousing26 are typically free of any user input components (e.g., buttons/interfaces/electromechanical switches) that would allow the user to program local processor20), thus reducing the size, complexity and cost ofinfusion pump10. Alternatively,infusion pump10 may include an integrated user interface (not shown) with some or all of the features ofremote controller100, thus allowing the user to directly input instructions/commands toinfusion pump10.
• Remote controller100 typically includes: user input components that allow the user to provide information; user output components that allow the user to receive information; a processor (hereinafter referred to as the “remote” processor) coupled to the user input components and the user output components and configured to provide instructions to the infusion pump; and one or more computer programs that provide instructions to the remote processor.
• The computer programs instruct the remote processor to receive information from the user via the user input components, provide information to the user via the user output components, and provide instructions/commands toinfusion pump10.
• As shown inFIG. 5, the user input components may include: electromechanical switches, such as three softkey selection switches102,104,106; an up/downnavigation toggle switch108; a “display user information”switch110; a power on/offswitch112; a “check pump status”switch114; and an “instant bolus”switch116. The user output components may include: a visual display (e.g., LCD screen118); a sound making device (e.g., a buzzer; not shown); and/or a vibrating element (not shown).
• Softkey selection switches102,104,106 causeremote controller100 to perform the action indicated by the label (on LCD screen118) above the switch in question. If there is no label above one of theswitches102,104,106, pressing the switch at that time will result in no activity. The up/downnavigation toggle switch108 is used to navigate a menu, enter a number, or change a character during text entry.
• LCD screen118 displays icons to distinguish between various features. For non-menu pages, the icon may be displayed in the upper-left corner ofLCD screen118. On menu pages, the icon may be displayed to the left of the currently highlighted menu item, except on the main menu where an icon is displayed to the left of all menu items.
• System functions are navigated via menus, which list the functions available to the user and allow the user to quickly enable the appropriate function. These menus consist of a set of options in a list, with a highlight that moves up and down in response to the up/downnavigation toggle switch108. When the highlight is over the appropriate option, the user depresses one of the three softkey selection switches102,104,106 to select the option. Text entry in the system is accomplished via thesoft keys102,104,106 and the up/downtoggle switch108. The user moves the flashing up/down icon left and right using two of the soft keys, and changes the character above the icon using the up/downnavigation toggle switch108. Pressing the up/downtoggle switch108 changes the letter to the next letter in the sequence.
• Although not shown,remote controller100 may include additional components such as an integrated glucose meter (e.g., a TheraSense® FreeStyle™ Glucose Meter that is available from Abbott Diabetes Care of Alameda, Calif.). If such additional components are includes, the user interface components ofremote controller100 are typically configured to operate the additional components.
• According to one embodiment,RF telemetry processor22 ofinfusion pump10 receives electronic communication fromremote controller100 using radio frequency or other wireless communication standards/protocols. In a preferred embodiment,RF telemetry processor22 is a bidirectional communication device, that includes a receiver portion and a transmitter portion. This, in turn, allowsinfusion pump10 to transmit information toremote controller100. In this embodiment,remote controller100 is also capable of bidirectional communication, thus allowingremote controller100 to receive the information sent byinfusion pump10.
• Local processor20 ofinfusion pump10 typically includes all of the computer programs and electronic circuitry needed to allow a user to programlocal processor20. Such circuitry may include one or more microprocessors, digital and/or analog integrated circuits, and other various passive and active electronic components, for example.
• As will be discussed below in greater detail,local processor20 also typically includes the programming, electronic circuitry and memory to activatedispenser assembly12 at the programmed time intervals. In a preferred embodiment, user instructions/commands are processed inremote controller100 to generate one or more specific flow control instructions, (i.e., drive signals) forinfusion pump10. Alternatively, the user may input the instructions/commands intoremote controller100, such that the instructions/commands are transmitted fromremote controller100 to infusion pump10, where the instructions/commands are processed to generate the flow control instructions (i.e., drive signals) forinfusion pump10.
• Referring toFIG. 6,local processor20 typically includesmain processing unit150 andinterlock processing unit152. Additionally, infusion pump10 typically also includesmain alarm unit154,interlock alarm unit156, RF telemetry processing unit22 (which includes RF (i.e., radio frequency)portion158 and a pass-through portion160).
• In order to conserve battery power, several of the components ofinfusion pump10 are maintained in a “sleep” mode that reduces power consumption.RF portion158 of RFtelemetry processing unit22 “wakes up” at predefined intervals (e.g., every 125 milliseconds) and polls a defined frequency (e.g., 13.56 megahertz) to determine ifremote controller100 is trying to communicate withinfusion pump10. If data packets are not available for receipt,RF portion158 of the RFtelemetry processing unit22 returns to “sleep” mode for the predefined interval.
• However, if a data packet is available for receipt,RF portion158 receives the data packet and examines it to verify that the packet was received from an authorized source. Typically, this verification is performed by examining the content of the data packet received to see if it contains a defined bit signature/validation sequence (e.g., 0110 0110, or 1001 1001). If present,RF portion158 transmits an acknowledgement signal toremote controller100 that requests transmission of the instruction set. Additionally,RF portion158 may verify that the data packet received is valid, which may be determined using, for example, a checksum.
• At this point,RF portion158 “wakes up”main processing unit150 and the data packets received are provided tomain processing unit150 for further examination and processing. Typically, “wake up” signals are transmitted between communicating devices (e.g.,main processing unit150,interlock processing unit152, and RFtelemetry processing unit22, for example) via the various buses (not shown) that interconnect the communicating devices.
• Main processing unit150 may reexamine the received data packet(s) to verify that infusion pump10 is truly the intended recipient of the data packet. As discussed above, one or more of the data packets received typically includes a unique bit signature/validation sequence that identifies the intended recipient of the data packet. If the unique bit signature/validation sequence within the packet does not match the unique bit signature/validation sequence ofinfusion pump10,infusion pump10 is not the intended recipient, the data packet is rejected bymain processing unit150, and themain processing unit150 notifies theRF portion158 of the RFtelemetry processing unit22 that the data packet received was misdirected.
• However, if infusion pump10 is indeed the intended recipient of the data packet,main processing unit150 accepts the data packet, as the received data packet is a portion of a valid instruction set being transmitted byremote controller100. This packet receipt and examination process continues for subsequently-received data packets until the instruction set received is complete. Once received, the complete instruction set includes a main instruction portion (for the main processing unit150) and an interlock instruction portion (for the interlock processing unit152).
• Once a complete instruction set is received,main processing unit150 wakes upinterlock processing unit152 so that the interlock portion of the received instruction set can be transferred to interlockprocessing unit152. Typically, each data packet received includes an interlock portion and a main portion (in addition to the identification information described above). The interlock portion (for use by interlock processing unit152) typically includes instructions in terms of pulses of medicament (e.g., insulin) per unit time (e.g., per half hour). The main portion (for use by main processing unit150) typically includes instructions in terms of the number of partial pulses of medicament (e.g., insulin), and the delay between each partial pulse.
• As stated above, RFtelemetry processing unit22 includes pass-throughportion160 that allows for pass-through communications betweenmain processing unit150 andinterlock processing unit152, and betweeninterlock processing unit152 and interlockalarm unit156. As will be discussed below, pass-throughportion160 of RFtelemetry processing unit22 acts as a conduit that completes a circuit between the communicating devices, in thatRF portion158 of RFtelemetry processing unit22 is isolated from and does not modify the signals passed between the communicating devices.
• Additionally, pass-throughportion160 of RFtelemetry processing unit22 includes status registers162,164 that are readable and writable by devices external to RFtelemetry processing unit22. As will be discussed below, status registers162,164 included in RFtelemetry processing unit22 allow main andinterlock processing units150,152 to confirm the operation ofdispenser assembly12 and, in the event of a failure, prevent the pump drive signals from reachingdispenser assembly12.
• As stated above, once a complete instruction set is received, the interlock portion of the instruction set is transferred to interlockprocessing unit152. In the event that interlock processingunit152 does not acknowledge receipt of the interlock portion of the instruction set,main processing unit150 assumes thatinterlock processing unit152 is malfunctioning and initiates an alarm onmain alarm unit154.
• Interlock processing unit152 andmain processing unit150 are typically powered by separate power supplies (e.g., batteries or capacitors; not shown), are synchronized using a common clock (not shown), and each independently execute their received instruction sets, resulting in a level of redundancy.
• Often, a received instruction set will specify that a defined dose of medicament be dispensed at predefined intervals (e.g., ten minutes). At the expiration of one of these predefined intervals,main processing unit150 contacts (via pass-throughportion160 of RF telemetry processing unit22)interlock processing unit152 to confirm that it is the proper time for dispensing the defined dose of medicament. Ifinterlock processing unit152 fails to respond,main processing unit150 assumes thatinterlock processing unit152 is malfunctioning and initiates an alarm onmain alarm unit154.
• Further, in the event that interlock processingunit152 does not agree that it is the proper time to dispense the defined dose of medicament,interlock processing unit152 may initiate an alarm oninterlock alarm unit156, via pass-throughportion160 of RFtelemetry processing unit22. Additionally and/or alternatively,main processing unit150 may initiate an alarm onmain alarm unit154.
• If bothinterlock processing unit152 andmain processing unit150 concur that it is time to dispense the defined dose of medicament,main processing unit150 provides the appropriate “pump drive signal” todispenser assembly12.
• Afterdispenser assembly12 completes dispensing the medicament, a completion signal is provided bydispenser assembly12 to status register162 to confirm that the medicament was successfully dispensed.Main processing unit150 andinterlock processing unit152 monitor status register162 to determine if the medicament was dispensed. If, after a defined period of time (e.g., 1-5 seconds),status register162 fails to indicate that the medicament was dispensed,main processing unit150 assumes thatdispenser assembly12 is malfunctioning andmain processing unit150 typically initiates an alarm onmain alarm unit154. Additionally and/or alternatively,interlock processing unit152 may initiate an alarm on interlock alarm unit156 (via pass-throughportion160 of RF telemetry processing unit22).
• In addition to the alarms, in the event that dispenserassembly12 fails to dispense the medicament, the main and/orinterlock processing units150,152 may provide a dispenser failure signal to a second status register164. The value of register164 determines whether a relay166 (e.g., a FET transistor) that is in thesignal line168 that provides the “pump drive signal” todispenser assembly12 is energized. Accordingly, in the event that thedispenser assembly12 fails to dispense the defined medicament dose,dispenser assembly12 is electrically disconnected from thesignal line168 controllingdispenser assembly12.
• When RFtelemetry processing unit22 andremote controller100 communicate by transmitting an RF data signal acrosswireless communication channel170, this communication typically occurs across a non-restricted frequency band, which is a frequency band that is dedicated to public use and not restricted for use by only a certain class of devices. For example, a restricted frequency band is 408-412 megahertz, which is reserved in the United States for the exclusive use of medical devices. An example of a non-restricted frequency band is 13.40-13.70 megahertz, which is dedicated for public use worldwide and has no use device-class restrictions. Specifically, RFtelemetry processing unit22 andremote controller100 typically communicate using a 13.56 megahertz carrier signal, onto which the individual data packets within the instruction set are encoded.
• RFtelemetry processing unit22 is electrically coupled toantenna assembly172, which facilitates wireless communication withremote controller100. As it is desirable to minimize the size ofinfusion pump10,antenna172 is typically a compact antenna design (e.g., a spirally-wound antenna or a helically-wound antenna). As is known in the art, it is desirable for the effective length ofantenna172 to be a defined percentage (e.g., 25%, 50% or 100%) of the wavelength of the carrier signal. For a carrier signal of 13.56 megahertz, the wavelength of the carrier signal is 22.100 meters and, therefore, the defined percentages are 5.525 meters, 11.050 meters, and 22.100 meters, respectively.
• Since it is desirable to reduce the physical size ofinfusion pump10,main processing unit150 and RFtelemetry processing unit22 are typically incorporated into asingle microchip174, such as an ASIC (i.e., application specific integrated circuit). Ifmain processing unit150 and RFtelemetry processing unit22 are incorporated into a single microchip, two separate power supplies (not shown) may be required to power the microchip, a first power supply formain processing unit150 and a second power supply for RFtelemetry processing unit22. Alternatively or additionally, it may be desirable to incorporateinterlock processing unit152, RFtelemetry processing unit22, andmain processing unit150 into asingle microchip174′ (shown in phantom). Since, by design,main processing unit150 andinterlock processing unit152 are powered by separate power supplies, if all three processingunits150,152,22 are incorporated into a single microchip, three power supplies may be required topower microchip174′.
• When incorporating two of more processing units (e.g.,main processing unit150,interlock processing unit152, and/or RF telemetry processing unit22) within asingle microchip174, it may be desirable to locateantenna172 outside ofmicrochip174, thus reducing the risk of electromagnetic interference withinmicrochip174. Further, if RFtelemetry processing unit22 includes a boost circuit176 (i.e., to boost the amplitude of the signal broadcast or received by antenna172), it may be desirable to also locateboost circuit176 external tomicrochip174 in order to shieldmain processing unit150 and/orinterlock processing unit152 from electromagnetic interference.
• Dispenser assembly12 typically includes a fill sensor24 (e.g., a normally open mechanical switch) that provide an initialization signal to local processor20 (i.e.,main processing unit150 and/or interlock processing unit152). As stated above,dispenser assembly12 includes afluid reservoir14 having a plunger (not shown) that moves axially, such that the direction of movement of the plunger is dependant upon whether thefluid reservoir14 is being filled or emptied. Prior to use ofinfusion pump10,fluid reservoir14 must be filled with medicament, as it is typically shipped from the factory empty.
• Prior to fillingfluid reservoir14 ofdispenser assembly12 with medicament,infusion pump10 is in an inactive state, thereby reducing power consumption and lengthening shelf life. When it is time to useinfusion pump10, the patient must fill thefluid reservoir14 ofdispenser assembly12 with medicament. Oncefluid reservoir14 is filled with at least a predefined volume of medicament (e.g., 50 units), the plunger of thefluid reservoir14 contacts fillsensor24, thereby providing the initialization signal tolocal processor20. At this point, the various components ofinfusion pump10 are initialized and begin to operate as described above.
• A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. Accordingly, other implementations are within the scope of the following claims.

Claims (24)

1. A system for delivering a fluid to a patient comprising:

a remote controller; and

an infusion pump including:

an RF telemetry portion configured to receive an RF data signal from the remote controller;

a processing portion configured to process the RF data signal received by the RF telemetry portion; and

a dispensing apparatus, responsive to the processing portion of the medical device, for dispensing medicament in accordance with the RF data signal;

wherein the dispensing apparatus includes a fill sensor for providing an initialization signal to the processing portion of the medical device upon the dispensing apparatus being filled with at least a defined volume of medicament.

2. The system ofclaim 1 wherein the defined volume of medicament is fifty units.

3. The system ofclaim 1 wherein the medicament is insulin.

4. The system ofclaim 1 wherein the dispensing apparatus includes a fluid reservoir and the fill sensor is a normally open mechanical switch that closes upon the reservoir being filled with the at least a defined volume of medicament.

5. A medical device comprising:

an RF telemetry portion configured to receive an RF data signal;

a processing portion configured to process the RF data signal received by the RF telemetry portion; and

a dispensing apparatus, responsive to the processing portion of the medical device, for dispensing medicament in accordance with the RF data signal;

wherein the dispensing apparatus includes a fill sensor for providing an initialization signal to the processing portion of the medical device upon a fluid reservoir of the dispensing apparatus being filled with at least a defined volume of medicament.

6. The medical device ofclaim 5 wherein the defined volume of medicament is about one half of the reservoir volume.

7. The medical device ofclaim 5 wherein the medicament is insulin.

8. The medical device ofclaim 5 wherein the fill sensor is a normally-open mechanical switch that closes upon the fluid reservoir being filled with the at least a defined volume of medicament.

9. The medical device ofclaim 5 wherein, upon receipt of the initialization signal by the processing portion, the RF telemetry portion periodically polls a defined RF frequency to determine if the RF data signal is available for receipt.

10-12. (canceled)

13. The medical device ofclaim 5 wherein the RF telemetry portion includes compact antenna.

14. The medical device ofclaim 13 wherein the compact antenna is a spirally-wound antenna.

15. The medical device ofclaim 13 wherein the compact antenna is a helically-wound antenna.

16. The medical device ofclaim 13 wherein an effective length of the compact antenna is a defined percentage of a wavelength of a carrier signal.

17. The medical device ofclaim 5 wherein the processing portion includes:

a main processing unit; and

an interlock processing unit.

18. The medical device ofclaim 5 wherein the RF data signal includes a defined validation sequence and the RE telemetry portion is further configured to:

examine the RF data signal to confirm that the RF data signal includes the defined validation sequence.

19. The medical device ofclaim 18 wherein the RF telemetry portion is further configured to:

transmit an acknowledgement signal to the device transmitting the RF data signal if it is determined that the RF data signal includes the defined validation sequence.

20. The medical device ofclaim 5 wherein the RF telemetry portion and at least a first portion of the processing portion are incorporated into a single microchip.

21. The medical device ofclaim 20 wherein the single microchip is an application-specific integrated circuit.

22. A method of extending the shelf life of a medical device comprising:

placing the medical device into a low-power sleep mode, wherein the medical device includes a processing portion and a dispensing apparatus;

filing the dispensing apparatus with at least a defined volume of medicament; and

providing an initialization signal to the processing portion of the medical device.

23. The method ofclaim 22 wherein the medical device includes an RF telemetry portion, the method further comprising:

periodically polling a defined RF frequency, via the RF telemetry portion, to determine if an RF data signal is available for receipt.

24. (canceled)

25. The method ofclaim 23 wherein the RF data signal is available for receipt and the RF data signal includes a defined validation sequence, the method further comprising:

examining the RF data signal to confirm that the RF data signal includes the defined validation sequence.

26. The method ofclaim 25 further comprising:

transmitting an acknowledgement signal to the device transmitting the RF data signal if it is determined that the RF data signal includes the defined validation sequence.

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